Reza Siahmsnsour; Hossein Arzani; Mohammad Jafari; Seyed Akbar Javadi; Ali Tavili
Abstract
The fire is one of the factors that have effect on the natural cycle of ecosystem. This project was established to deal with the effect of the fire on quality features of habitat in the research site of rangelands plants of Zagheh Gorge.It was occur at Khoramabad northeast 35 Km with 33° 29" N, and ...
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The fire is one of the factors that have effect on the natural cycle of ecosystem. This project was established to deal with the effect of the fire on quality features of habitat in the research site of rangelands plants of Zagheh Gorge.It was occur at Khoramabad northeast 35 Km with 33° 29" N, and 48° 42" E, being at 1960 meters above the sea level. This study was formed by travel method, We Used Transects 200 m and plots 1 m that chose vegetation type and plants morphology Both Control area and treatment in Comparison Conclusion show that there are difference significant between canopy cover in the control area, and the fire (p<0.01). Also, after two years, there are not difference significant between organic matter, litter, pebble and rock (p<0.01). But there are significant difference between Soil Conservation level inside and outside of the fire area (p<0.01).This Statistics show that there are difference between the plant production of Class I and III in the control area and the fire with 30.32 and 5.54 in control area and 24.84 and 2.72 gr/m2 in the fire area (p<0.01). The Control area with 69.32 Percent of Canopy Cover is better than the fire area with 51.6(p<0.01) so, high percent of Canopy cover in the Control treatment caused heap of crucibles and numerous branches in this area. Forbs plants, decreased from 46.8 % in the control Canopy Cover area to 35.6 % in the fire area; whereas, grasses increased from 53.2 percent in the control area to 64.4 percent in the fire area. So, the fire is effective on increase of grasses and decrease of forbs.
Mohammad Hemmati; Davood Nikkami; Hassan Ahmadi; Gholamreza Zehtabian; Mohammad Jafari
Volume 1, Issue 1 , May 2009, , Pages 21-31
Abstract
Soil is one of the four elements of life and one of the most important agricultural and rangeland production factors. Soil erosion has impact on fertility of upstream lands and indirectly causes downstream damages. On a global scale, more than 50% of rangelands and about 80% of farmlands are significantly ...
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Soil is one of the four elements of life and one of the most important agricultural and rangeland production factors. Soil erosion has impact on fertility of upstream lands and indirectly causes downstream damages. On a global scale, more than 50% of rangelands and about 80% of farmlands are significantly suffering from soil erosion and sedimentation phenomenon. Despite of agricultural benefits of rainwater, its erosive energy in the primary stages, detaches soil particles and creates surface runoff which has the most severe impacts on soil erosion. The effective energy in this shape of erosion is called rainfall erosivity, which is rainfall erosion potential and depends on rainfall physical characteristics. Some different indices are developed for quantification of rainfall erosivity. Some indices emphasise on the amount of rainfall or rain intensity. Worldwide investigations show that applying a certain index, like EI60 in USLE equation has not sufficient credit and according to climatic condition the best rainfall erosivity index should be determined. In this research, after establishing 21 erosion plots in Kaboudeh Oliya village, Kermanshah city, on two land use types of dry farming of 6, 12, 16 and 17 percent slopes and rangelands on 25, 35 and 45 percent slopes with three repetitions, 15 rainfall events which produced surface runoff were monitored by a recording rain gauge and the amount of surface runoff and sediment were measured. According to the literature, 45 rainfall erosivity indices were chosen to be compared. For facilitating and increasing accuracy of calculations on rainfall erosivity indices, a computer program was developed to analyze and extract necessary factors from each storm. The result showed that in the study area, EI60 is the best rainfall erosivity index and has maximum correlation coefficient of 0.721 with soil loss.
